Optokinetic Motion Sickness And Pseudo-Coriolis Effects Induced By Moving Visual Stimuli

Abstract

Pseudo-Coriolis effects (PCE) and optokinetic motion sickness are elicited by bending the head out of the axis of rotation of a circular visual surround when that moving surround induces the illusion of self-rotation. With respect to tilt sensation and vegetative symptoms, optokinetic PCE correspond to vestibular Coriolis effects (CE) that arise from similar head movements when the body is actually rotating. Quantitatively, PCE are of smaller magnitude than CE and saturate at lower velocities of stimulation (90-120°/sec). PCE, depending on the illusory sensation of self-rotation (circularvection, CV), share its prolonged time course after stimulus onset and termination, its relation to stimulus velocities and its dependency on stimulus area with predominance of the retinal periphery. Optokinetic influences on vestibular CE depend on the direction and speed of the moving visual stimulus and result in either inhibition or facilitation of apparent tilt and nausea.